WO2011034155A1

WO2011034155A1 - Skin material for vehicle interior member

Info

Publication number: WO2011034155A1
Application number: PCT/JP2010/066105
Authority: WO
Inventors: 祐之松田; 正雄原; 嗣久宮本; 孝宏栃岡; 力弥安孫子; 宏和林; 清綱豊原
Original assignee: マツダ株式会社; 帝人ファイバー株式会社; 帝人株式会社
Priority date: 2009-09-16
Filing date: 2010-09-10
Publication date: 2011-03-24
Also published as: JP2011063898A

Abstract

Disclosed is a skin material for a vehicle interior member, which is configured of a fabric that has been dyed and contains polylactic acid filaments. The skin material for a vehicle interior member has excellent fabric strength even after being exposed in a wet heat environment. Specifically disclosed is a skin material for a vehicle interior member, which is configured of a fabric that has been dyed and contains polylactic acid filaments, and which has a tensile strength of not less than 400 N/50 mm as measured in accordance with JIS L1096.8.12 (1999) after being exposed to an environment at a temperature of 50°C and at a humidity of 95% RH for 1,000 hours.

Description

Skin material for vehicle interior parts

The present invention relates to a vehicle interior member skin material composed of a fabric containing polylactic acid filaments and subjected to a dyeing process, and has an excellent fabric strength even after being exposed to a humid heat environment. It relates to the skin material.

Polylactic acid filaments are attracting attention in recent years as fibers that are friendly to the global environment because the raw material lactic acid or lactide is produced from natural products, and these polylactic acid filaments can be used in various applications such as vehicle interior parts. (See, for example, Patent Document 1 and Patent Document 2).
However, polylactic acid filaments are generally inferior in heat and moisture resistance compared to petroleum-derived aromatic polyesters such as polyethylene terephthalate, so that when used as a skin material for vehicle interior members exposed to harsh environments, the fabric of a skin material for vehicle interior members There was a problem that the strength was lowered. In particular, since the skin material for vehicle interior members is usually dyed, the fiber strength of the polylactic acid filaments is reduced by wet heat during the dyeing process, and the fabric strength of the skin material for vehicle interior members is further reduced. There was a problem to do.
JP 2008-57095 A JP 2009-30217 A

The present invention has been made in view of the above-mentioned background, and an object of the present invention is a skin material for a vehicle interior member composed of a fabric containing a polylactic acid filament and subjected to a dyeing process, which is exposed to a wet heat environment. Another object of the present invention is to provide a vehicle interior member skin material having excellent fabric strength even after being applied.
As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that the fiber strength due to the dyeing process can be suppressed by shortening the dyeing time when dyeing the cloth containing the polylactic acid filament. The present invention has been completed by finding more headlines and further studies.
Thus, according to the present invention, “a vehicle interior material composed of a fabric containing polylactic acid filaments and subjected to a dyeing process, which was exposed to an environment of temperature 50 ° C. and humidity 95% RH for 1,000 hours. A skin material for a vehicle interior member characterized in that the subsequent tensile strength is 400 N / 50 mm or more.
However, the said tensile strength shall measure the tensile strength of the skin | leather material for vehicle interior members according to JISL1096.8.12 (1999 version).
At that time, the polylactic acid filament is composed of (i) poly L-lactic acid having a weight average molecular weight of 50,000 to 300,000 (component A), and (ii) poly D-lactic acid having a weight average molecular weight of 50,000 to 300,000 (component B). And (iii) A filament containing a phosphoric acid ester metal salt represented by the following formula (1) or (2) in an amount of 0.05 to 5 parts by weight per 100 parts by weight of the total of the A component and the B component. .

In the formula, R ₁ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ₂ and R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and M ₁ represents an alkali metal atom or Represents an alkaline earth metal atom, and p represents 1 or 2.

In the formula, each of R ₄ , R ₅ and R ₆ independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, M ₂ represents an alkali metal atom or an alkaline earth metal atom, and p represents 1 or 2 Represents.
The polylactic acid filament is preferably a false twist crimped yarn. Moreover, it is preferable that the said fabric is a woven fabric whose cover factor (CF) represented by a following formula is 1,800 or more.
CF = (DWp / 1.1) ^1/2 × MWp + (DWf / 1.1) ^1/2 × MWf
However, DWp is the total warp fineness (dtex), MWp is the warp weave density (main / 2.54 cm), DWf is the total weft fineness (dtex), and MWf is the weft weave density (main / 2.54 cm). The fabric is preferably a knitted fabric of 30 to 100 courses / 2.54 cm and 20 to 60 wales / 2.54 cm.
Further, it is preferable that the conditions of the dyeing process are a temperature of 110 to 140 ° C. and a time of 19 minutes or less. Moreover, it is preferable that 0.3% by weight or more of the resin is fixed to the cloth by an impregnation method with respect to the weight of the cloth. At that time, the resin is preferably a silicon resin, a polyethylene resin, or a polyethylene terephthalate resin. Moreover, it is preferable that a backing resin is applied to the fabric at an application amount of 30 g / m ² or more. In that case, it is preferable that the backing resin contains an acrylic resin.
According to the present invention, (i) poly L-lactic acid (A component) having a weight average molecular weight of 50,000 to 300,000, poly D-lactic acid (B component) having a weight average molecular weight of 50,000 to 300,000, and A component and B component A fabric containing a polylactic acid filament containing 0.05 to 5 parts by weight of a phosphoric acid ester metal salt per 100 parts by weight in total with a temperature of 110 to 140 ° C. under conditions of 19 minutes,
(Ii) impregnating the dyed fabric with resin,
(Iii) applying a backing resin to the fabric impregnated with the resin;
The manufacturing method of the skin material for vehicle interior members including each process is provided.
In the manufacturing method, the fabric is preferably a woven fabric having a cover factor (CF) represented by the following formula of 1,800 or more.
CF =
(DWp / 1.1) 1/2 * MWp + (DWf / 1.1) 1/2 * MWf
(However, DWp is the warp total fineness (dtex), MWp is the warp weave density (main / 2.54 cm), DWf is the total weft fineness (dtex), and MWf is the weft weave density (main / 2.54 cm).
The fabric is preferably a knitted fabric of 30 to 100 courses / 2.54 cm and 20 to 60 wales / 2.54 cm.

FIG. 1 is a diagram schematically showing a state in which a backing resin is applied to a fabric in a vehicle interior material according to the present invention.

1: Fabric 2: Backing resin

Hereinafter, the present invention will be described in detail.
The skin material for vehicle interior members of the present invention is a skin material for vehicle interior members composed of a fabric containing polylactic acid filaments and subjected to dyeing, and is in an environment of a temperature of 50 ° C. and a humidity of 95% RH. A skin material for a vehicle interior member having a tensile strength of 400 N / 50 mm or more after being exposed for 1,000 hours. However, the said tensile strength shall measure the tensile strength of the skin | leather material for vehicle interior members according to JISL1096.8.12 (1999 version). When the tensile strength is less than 400 N / 50 mm, the fabric strength decreases with time when using the vehicle interior member skin material, which is not preferable because of lack of practicality. The tensile strength is preferably as large as possible, but practically, it may be 1,000 N / 50 mm or less.
The skin material for a vehicle interior member according to the present invention can be manufactured, for example, by the following method.
(Polylactic acid)
First, the polylactic acid filament used in the present invention is a filament made of polylactic acid comprising a poly L-lactic acid component and / or a poly D-lactic acid component. In particular, it is preferable to use a poly L-lactic acid component and a poly D-lactic acid component having crystallinity, and a filament made of a poly L-lactic acid component having a high optical purity and a polylactic acid composition composed of a poly D-lactic acid component is preferable.
Particularly preferably, a crystalline poly L-lactic acid component or poly D-lactic acid component having a melting point of 160 ° C. or higher can be suitably used.
The poly L-lactic acid component is preferably 90 to 100 mol%, more preferably 95 to 100 mol% of L-lactic acid units, and 99 to 100 mol% for realizing a high melting point, in addition to the degree of stereoization. Is preferred, it is more preferably composed of 95 to 99 mol% of L-lactic acid units. Examples of other units include D-lactic acid units and copolymer component units other than lactic acid. The D-lactic acid unit and the copolymer component unit other than lactic acid are preferably 0 to 10 mol%, more preferably 0 to 5 mol%, still more preferably 0 to 2 mol%, and particularly preferably 0 to 1 mol%. .
The poly-D-lactic acid component is preferably 90 to 100 mol%, more preferably 95 to 100 mol% of D-lactic acid units, and 99 to 100 mol% for realizing a high melting point, and in addition, the degree of stereoization is increased. If preferred, it is more preferably composed of 95 to 99 mol% of D-lactic acid units. Examples of other units include L-lactic acid units and copolymer component units other than lactic acid. The L-lactic acid unit and the copolymer component unit other than lactic acid are preferably 0 to 10 mol%, more preferably 0 to 5 mol%, still more preferably 0 to 2 mol%, and particularly preferably 0 to 1 mol%. .
The copolymer component unit is a unit derived from dicarboxylic acid, polyhydric alcohol, hydroxycarboxylic acid, lactone, etc. having a functional group capable of forming two or more ester bonds, and various polyesters, various polyethers composed of these various components, Examples are derived from various polycarbonates and the like.
Examples of the dicarboxylic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, terephthalic acid, and isophthalic acid. Polyhydric alcohols include ethylene glycol, propylene glycol, propanediol, butanediol, pentanediol, hexanediol, octanediol, glycerin, sorbitan, neopentyl glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol Aliphatic polyhydric alcohols such as aliphatic polyhydric alcohols, and aromatic polyhydric alcohols obtained by adding ethylene oxide to bisphenol. Examples of the hydroxycarboxylic acid include glycolic acid, hydroxybutyric acid, 4-hydroxybenzoic acid and the like. Examples of the lactone include glycolide, ε-caprolactone glycolide, ε-caprolactone, β-propiolactone, δ-butyrolactone, β- or γ-butyrolactone, pivalolactone, δ-valerolactone, and the like.
The poly L-lactic acid component and the poly D-lactic acid component both have a weight average molecular weight of preferably 100,000 to 500,000, more preferably 150,000 to 350,000. Further, if it is 10% by weight or less based on the polymer weight, other components may be blended.
The poly L-lactic acid and poly D-lactic acid can be produced by a known method.
For example, L- or D-lactide can be produced by heating and ring-opening polymerization in the presence of a metal polymerization catalyst. Moreover, after crystallizing low molecular weight polylactic acid containing a metal polymerization catalyst, it can be produced by solid phase polymerization by heating under reduced pressure or in an inert gas stream. Further, it can be produced by a direct polymerization method in which lactic acid is subjected to dehydration condensation in the presence / absence of an organic solvent.
The polymerization reaction can be carried out in a conventionally known reaction vessel. For example, a vertical reactor or a horizontal reactor equipped with a stirring blade for high viscosity, such as a helical ribbon blade, can be used alone or in parallel. Moreover, any of a batch type, a continuous type, a semibatch type may be sufficient, and these may be combined.
Alcohol may be used as a polymerization initiator. Such alcohol is preferably non-volatile without inhibiting the polymerization of polylactic acid. For example, decanol, dodecanol, tetradecanol, hexadecanol, octadecanol and the like can be suitably used.
In the solid phase polymerization method, a relatively low molecular weight lactic acid polyester obtained by the above-described ring-opening polymerization method or lactic acid direct polymerization method is used as a prepolymer. It can be said that the prepolymer is preferably crystallized in advance in the temperature range of the glass transition temperature (Tg) or higher and lower than the melting point (Tm) from the viewpoint of preventing fusion. The crystallized prepolymer is filled in a fixed vertical or horizontal reaction vessel, or a reaction vessel (rotary kiln, etc.) where the vessel itself rotates like a tumbler or kiln, and the prepolymer glass transition temperature (Tg) or higher. Heated to a temperature range below the melting point (Tm). There is no problem even if the polymerization temperature is raised stepwise as the polymerization proceeds. In addition, for the purpose of efficiently removing water generated during solid phase polymerization, a method of reducing the pressure inside the reaction vessels or circulating a heated inert gas stream is also preferably used.
The metal-containing catalyst used at the time of polylactic acid polymerization is preferably deactivated with a conventionally known deactivator. Examples of such a deactivator include an organic ligand consisting of a group of chelate ligands having an imino group and capable of coordinating to a polymerized metal catalyst, dihydridooxoline (I) acid, dihydridotetraoxodilin (II, II ) Acid, hydridotrioxoline (III) acid, dihydridopentaoxodiphosphoric acid (III, III) acid, hydridopentaoxodiphosphoric acid (II, IV) acid, dodecaoxohexaphosphorus (III) acid, hydridooctaoxotriphosphorus ( III, IV, IV) acid, octaoxotriphosphoric acid (IV, III, IV), hydridohexaoxodiphosphoric acid (III, V), hexaoxodiphosphoric acid (IV), decaoxotetralinic acid (IV), hendecaoxotetra Low oxidation number phosphoric acid having an acid number of 5 or less, such as phosphoric (IV) acid, eneoxotriphosphorus (V, IV, IV) acid, formula xH ₂ O ・ yP ₂ O ₅ X / y = 3 orthophosphoric acid, 2> x / y> 1, and polyphosphoric acid called diphosphoric acid, triphosphoric acid, tetraphosphoric acid, pentaphosphoric acid, etc., based on the degree of condensation, and these Mixture, metaphosphoric acid represented by x / y = 1, especially trimetaphosphoric acid, tetrametaphosphoric acid, 1> x / y> 0, ultra having a network structure with a part of the phosphorus pentoxide structure Phosphoric acid (sometimes collectively referred to as metaphosphoric acid compounds), and acid salts of these acids, mono- and polyhydric alcohols, or partial esters of polyalkylene glycols, complete ethers, phosphono Examples thereof include substituted lower aliphatic carboxylic acid derivatives.
From the catalyst deactivation ability, the formula xH ₂ O ・ yP ₂ O ₅ X / y = 3 orthophosphoric acid, 2> x / y> 1, and polyphosphoric acid called diphosphoric acid, triphosphoric acid, tetraphosphoric acid, pentaphosphoric acid, etc., based on the degree of condensation, and these Mixture, metaphosphoric acid represented by x / y = 1, especially trimetaphosphoric acid, tetrametaphosphoric acid, 1> x / y> 0, ultra having a network structure with a part of the phosphorus pentoxide structure Phosphoric acid (sometimes collectively referred to as metaphosphoric acid compounds), acidic salts of these acids, monovalent and polyhydric alcohols, or partial ester phosphorus oxoacids of polyalkylene glycols or these The acidic esters, phosphono-substituted lower aliphatic carboxylic acid derivatives and the above-mentioned metaphosphoric acid compounds are preferably used.
The metaphosphoric acid compound is a cyclic metaphosphoric acid in which about 3 to 200 phosphoric acid units are condensed, an ultra-regional metaphosphoric acid having a three-dimensional network structure, or a salt thereof (alkal metal salt, alkaline earth metal salt, onium salt). Is included.
Among them, cyclic sodium metaphosphate, ultra-region sodium metaphosphate, phosphono-substituted lower aliphatic carboxylic acid derivative dihexylphosphonoethyl acetate (hereinafter sometimes abbreviated as DHPA) and the like are preferably used.
The lactide content of the polylactic acid composition is selected in the range of 0 to 700 ppm. More preferably, a range of 0 to 500 ppm, more preferably 0 to 200 ppm, and particularly preferably 0 to 100 ppm is selected.
This is because when polylactic acid has a lactide content in such a range, the stability at the time of melting can be improved, and the advantages of efficient and stable spinning and the hydrolysis resistance of the fiber product can be enhanced.
In order to reduce the lactide content to such a range, a conventionally known lactide reduction treatment or a combination thereof is performed at any stage from the polymerization of poly L-lactic acid and poly D-lactic acid to the end of polylactic acid production. Can be achieved.
The polylactic acid composition preferably has a weight average molecular weight of 100,000 to 500,000. More preferably, it is 100,000 to 300,000. Even more preferably, it is 105,000 to 250,000.
The ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the polylactic acid composition is referred to as molecular weight dispersion (Mw / Mn). A large molecular weight dispersion means that there are many ratios of large molecules and small molecules compared to the average molecular weight.
That is, in a polylactic acid composition having a large molecular weight dispersion, for example, a composition having a weight average molecular weight of about 250,000 and a molecular weight dispersion of more than 3, the ratio of molecules having a weight average molecular weight value of more than 250,000 may increase. In such a case, the melt viscosity becomes large, which is not preferable in the spinning and stretching processes. In addition, in a polylactic acid composition having a relatively small weight average molecular weight of about 100,000 and a large molecular weight dispersion, the proportion of molecules having a weight average molecular weight value of less than 100,000 may increase. In this case, the durability of the mechanical properties of the fiber is increased. This is not preferable in use. From this viewpoint, the range of molecular weight dispersion is preferably 1.5 to 3.0, more preferably 1.5 to 2.5, and still more preferably 1.6 to 2.5.
A weight average molecular weight and a number average molecular weight are a weight average molecular weight and a number average molecular weight in terms of standard polystyrene as measured by gel permeation chromatography (GPC) using chloroform as an eluent.
The weight ratio of the poly L-lactic acid component to the poly D-lactic acid component in the polylactic acid composition is preferably in the range of 90:10 to 10:90. It is more preferably in the range of 75:25 to 25:75, still more preferably in the range of 60:40 to 40:60, and preferably as close to 50:50 as possible.
The polylactic acid composition preferably contains a stereocomplex polylactic acid composed of a poly L-lactic acid component and a poly D-lactic acid component. Here, the content rate of stereocomplex polylactic acid, that is, the degree of stereoification, is the ratio of the peak corresponding to the melting of the stereocomplex crystal in the melting peak in the temperature rising process in the differential scanning calorimeter (DSC) measurement, It is represented by the following formula (a), preferably 80 to 100%, more preferably 95 to 100%.
The melting point in the present invention is a crystal melting peak temperature measured by DSC, and the latter is used when a low temperature crystal melting peak temperature and a stereocomplex crystal melting peak temperature exist. It is important that the temperature is 195 ° C. or higher (preferably in the range of 195 to 250 ° C., more preferably 200 to 240 ° C.). The stereocomplex crystal melting enthalpy is preferably 20 J / g or more (more preferably 30 J / g or more).
Stereo level =
[(ΔHms / ΔHms0) / (ΔHmh / ΔHmh0 + ΔHms / ΔHms0)] × 100 (a)
(However, ΔHms0 = 203.4 J / g, ΔHmh0 = 142 J / g, ΔHms = melting enthalpy of stereocomplex melting point, ΔHmh = melting enthalpy of homocrystal)
The polylactic acid composition can be produced by mixing a poly L-lactic acid component alone or a poly L-lactic acid component and a poly D-lactic acid component in a predetermined weight ratio.
Mixing can be performed in the presence of a solvent. The solvent is not particularly limited as long as it dissolves poly L-lactic acid and poly D-lactic acid. For example, chloroform, methylene chloride, dichloroethane, tetrachloroethane, phenol, tetrahydrofuran, N-methylpyrrolidone, N, N-dimethylformamide, butyrolactone, trioxane, hexafluoroisopropanol or the like alone or in combination of two or more are preferred.
The mixing can be performed in the absence of a solvent. That is, a method of melt kneading after mixing a predetermined amount of poly L-lactic acid and poly D-lactic acid, or a method of adding and kneading one of them after melting one of them can be employed.
Alternatively, stereoblock polylactic acid in which a poly L-lactic acid segment and a poly D-lactic acid segment are bonded can also be suitably used as the polylactic acid composition.
Stereoblock polylactic acid is a block polymer in which a poly L-lactic acid segment and a poly D-lactic acid segment are bonded in the molecule.
Such block polymers include, for example, a method of producing by sequential ring-opening polymerization, a method of polymerizing poly (L-lactic acid) and poly (D-lactic acid), and then binding them with a chain exchange reaction or a chain extender. A block copolymer having the above-mentioned basic constitution such as a method of polymerizing L-lactic acid and poly-D-lactic acid and blending and then solid-phase polymerizing to chain-extend, a method of producing from racemic lactide using a stereoselective ring-opening polymerization catalyst, etc. Any polymer can be used regardless of the production method.
However, it is more preferable from the viewpoint of ease of production to use a high-melting stereoblock polymer obtained by sequential ring-opening polymerization and a polymer obtained by a solid phase polymerization method.
The polylactic acid composition and stereoblock polylactic acid used in the present invention preferably have a stereogenicity of 90% or more, more preferably 100%. The degree of stereoification can be determined by the above formula (a) by comparing the enthalpies of melting points in DSC measurement.
It is preferable to add a specific additive to the polylactic acid component used in the present invention in order to stably and highly promote the formation of a stereocomplex phase. For example, preferred examples include metal phosphates represented by the following formulas (1) and / or (2).

In formula (1), R ₁ Represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ₁ Examples of the alkyl group having 1 to 4 carbon atoms represented by the formula: methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group and the like.
R ₂ , R ₃ Each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. Examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, amyl group, tert-amyl group, hexyl group, heptyl group, octyl group, iso-octyl group, tert-octyl group, 2-ethylhexyl group, nonyl group, iso-nonyl group, decyl group, iso-decyl group, tert-decyl group, An undecyl group, a dodecyl group, a tert-dodecyl group, etc. are mentioned.
M ₁ Represents an alkali metal atom such as Na, K or Li or an alkaline earth metal atom such as Mg or Ca. p represents 1 or 2.
Among the phosphoric acid ester metal salts represented by the formula (1), for example, R ₁ Is a hydrogen atom, R ₂ , R ₃ Are both tert-butyl groups.

R in formula (2) ₄ , R ₅ , R ₆ Each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. Examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, amyl group, tert-amyl group, hexyl group, heptyl group, octyl group, iso-octyl group, tert-octyl group, 2-ethylhexyl group, nonyl group, iso-nonyl group, decyl group, iso-decyl group, tert-decyl group, An undecyl group, a dodecyl group, a tert-dodecyl group, etc. are mentioned.
M ₂ Represents an alkali metal atom such as Na, K or Li or an alkaline earth metal atom such as Mg or Ca. p represents 1 or 2.
Among the phosphoric acid ester metal salts represented by the formula (2), for example, R ₄ , R ₆ Is a methyl group, R ₅ Is a tert-butyl group. As a phosphoric acid ester metal salt, trade name “ADK STAB” NA-11 manufactured by ADEKA Co., Ltd. may be mentioned. The phosphoric acid ester metal salt can be synthesized by a known method.
As described in JP-A-2003-192884, the compound represented by the formula (1) or (2) is a compound known as a crystal nucleating agent for polylactic acid. However, in the present invention, M in the formulas (1) and (2) ₁ And M ₂ Is an alkali metal atom or an alkaline earth metal atom. M in Formula (1) and Formula (2) ₁ And M ₂ However, in the case of other metals such as aluminum, the heat resistance of the compound itself is low, and a sublimate is generated during spinning, which may be difficult to spin.
The phosphoric acid ester metal salt (component C) preferably has an average primary particle size of 0.01 to 10 μm, more preferably 0.05 to 7 μm. It is industrially difficult to make the particle size smaller than 0.01 μm, and it is not necessary to make it so small. On the other hand, if it is larger than 10 μm, the frequency of yarn breakage increases during spinning and drawing.
These metal salts are preferably used in an amount of 0.05 wt% to 5 wt%, more preferably 0.05 wt% to 0.5 wt%, still more preferably 0.05 wt% to 0.2 wt%, relative to the polylactic acid component. Is preferred. When the amount is too small, the effect of improving the degree of stereoization is small, and when too large, the resin itself is deteriorated, which is not preferable.
The polylactic acid component used in the present invention may or may not contain a moisture and heat resistance improver. When the polylactic acid component contains a heat and humidity resistance improver, a carboxyl group-capping agent having a specific functional group can be suitably applied as the heat and humidity resistance improver. Among these, a carbodiimide compound whose specific functional group is a carbodiimide group can be preferably selected from the viewpoints of effectively sealing the carboxyl group, promoting the formation of the color of the polylactic acid fiber structure, the formation of a stereocomplex phase, and heat and heat resistance.
That is, carbodiimide compounds include dicyclohexylcarbodiimide, diisopropylcarbodiimide, dimethylcarbodiimide, diisobutylcarbodiimide, dioctylcarbodiimide, octyldecylcarbodiimide, di-tert-butylcarbodiimide, tert-butylisopropylcarbodiimide, dibenzylcarbodiimide, N-octadecylimide N'-phenylcarbodiimide, N-benzyl-N'-phenylcarbodiimide, N-benzyl-N'-tolylcarbodiimide, di-o-toluylcarbodiimide, di-p-toluylcarbodiimide, bis (p-nitrophenyl) carbodiimide, bis (P-aminophenyl) carbodiimide, bis (p-hydroxyphenyl) carbodiimide, (P-chlorophenyl) carbodiimide, bis (o-chlorophenyl) carbodiimide, bis (o-ethylphenyl) carbodiimide, bis (p-ethylphenyl) carbodiimidebis (o-isopropylphenyl) carbodiimide, bis (p-isopropylphenyl) carbodiimide , Bis (o-isobutylphenyl) carbodiimide, bis (p-isobutylphenyl) carbodiimide, bis (2,5-dichlorophenyl) carbodiimide, p-phenylenebis (o-toluylcarbodiimide), p-phenylenebis (cyclohexylcarbodiimide, p- Phenylenebis (p-chlorophenylcarbodiimide), 2,6,2 ′, 6′-tetraisopropyldiphenylcarbodiimide, hexamethylenebis (cyclohexylcarbodiimide) ), Ethylenebis (phenylcarbodiimide), ethylenebis (cyclohexylcarbodiimide), bis (2,6-dimethylphenyl) carbodiimide, bis (2,6-diethylphenyl) carbodiimide, bis (2-ethyl-6-isopropylphenyl) Carbodiimide, bis (2-butyl-6-isopropylphenyl) carbodiimide, bis (2,6-diisopropylphenyl) carbodiimide, bis (2,6-di-tert-butylphenyl) carbodiimide, bis (2,4,6-trimethyl) Phenyl) carbodiimide, bis (2,4,6-triisopropylphenyl) carbodiimide, bis (2,4,6-tributylphenyl) carbodiimide, di-β-naphthylcarbosiimide, N-tolyl-N′-cyclohexylcarbosi Imide Mono- or di-carbodiimide compounds such as N- tolyl -N'- phenyl carbocyclylalkyl imide and the like.
Of these, bis (2,6-diisopropylphenyl) carbodiimide and 2,6,2 ′, 6′-tetraisopropyldiphenylcarbodiimide are preferred from the viewpoints of reactivity and stability. Of these, industrially available dicyclohexylcarbodiimide and diisopropylcarbodiimide are also suitable.
Also, poly (1,6-cyclohexanecarbodiimide), poly (4,4′-methylenebiscyclohexylcarbodiimide), poly (1,3-cyclohexylenecarbodiimide), poly (1,4-cyclohexylenecarbodiimide), poly (4 , 4′-diphenylmethanecarbodiimide), poly (3,3′-dimethyl-4,4′-diphenylmethanecarbodiimide), poly (naphthylenecarbodiimide), poly (p-phenylenecarbodiimide), poly (m-phenylenecarbodiimide), poly And polycarbodiimides such as (p-tolylcarbodiimide), poly (diisopropylcarbodiimide), poly (methyldiisopropylphenylenecarbodiimide), and poly (triethylphenylenecarbodiimide).
As the commercially available polycarbodiimide compound, for example, “Carbodilite” commercially available from Nisshinbo Co., Ltd. can be used. Specifically, “Carbodilite” LA-1 sold as a polylactic acid resin modifier, or “Carbodilite” HMV-8CA sold as a polyester resin modifier can be exemplified.
A carbodiimide compound can also be manufactured by a conventionally well-known method. For example, it can be produced by subjecting an organic isocyanate to a decarboxylation condensation reaction in a solvent-free or inert solvent at a temperature of 70 ° C. or higher using an organic phosphorus compound or an organometallic compound as a catalyst. The polycarbodiimide compound may be a conventionally known method for producing a polycarbodiimide compound, for example, US Pat. No. 2,941,956, Japanese Examined Patent Publication No. 47-33279, J. Pat. Org. Chem. 28, 2069-2075 (1963), Chemical Review 1981, Vol. 81 no. 4, p619-621 and the like.
The content of the carbodiimide compound is preferably 0.1 to 5.0 parts by weight, more preferably 0.5 to 2.0 parts by weight, per 100 parts by weight of the polylactic acid composition. A stereocomplex polylactic acid fiber containing a carbodiimide compound in such a range has a molecular weight retention of 95% or more after treatment in boiling water at 100 ° C. for 30 minutes, and a more preferable fiber can be obtained.
Moreover, application of a conventionally known carboxyl end group capping agent is also preferably selected.
In the present invention, the carboxyl group-reactive terminal blocking agent not only seals the terminal carboxyl group of the polylactic acid resin, but also includes a carboxyl group generated by the decomposition reaction of the polylactic acid resin and various additives, lactic acid, formic acid and the like. The carboxyl group of a low molecular compound can be sealed. Moreover, it is preferable that the said sealing agent is a compound which can seal | block the hydroxyl group terminal which an acidic low molecular weight compound produces | generates not only by a carboxyl group but by thermal decomposition, or the water | moisture content which penetrate | invades into a resin composition.
As the carboxyl end group blocking agent, it is preferable to use at least one compound selected from an epoxy compound, an oxazoline compound, an oxazine compound, and an isocyanate compound, and among them, an epoxy compound, an oxazoline compound, and an isocyanate compound are preferable.
As the epoxy compound, glycidyl ether compounds, glycidyl ester compounds, glycidyl amine compounds, glycidyl imide compounds, glycidyl amide compounds, and alicyclic epoxy compounds can be preferably used.
By containing a carboxyl end group capping agent, not only can the action of the carbodiimide compound be improved, but fibers that are excellent in spinnability, mechanical properties, heat resistance, and durability can be obtained.
In the polylactic acid composition of the present invention, the above-mentioned agent and various additives described later may be added and kneaded directly into the reaction vessel at any stage of the polymerization in the ring-opening polymerization method, preferably at a later stage of the polymerization. it can. In consideration of uniform dispersion in the polylactic acid composition and ability to prevent hue deterioration, kneading with an extruder or kneader is preferred. In other words, the polymer discharge port of the reactor can be connected to a uniaxial or multiaxial extruder and added. Examples thereof include a method of adding various agents to a polylactic acid composition formed into chips after polymerization or a polylactic acid powder after solid phase polymerization and kneading with an extruder or kneader.
At this time, various additives can be added directly into an extruder or kneader as a molten liquid, an aqueous solution, an organic solvent solution or a dispersion, or added to polylactic acid from a so-called side feeder.
It is also a preferred embodiment that the polylactic acid composition is kneaded with an extruder or kneader as a chip or a fine powder masterbatch.
(Spinning, drawing)
Next, a polylactic acid filament can be obtained by spinning and stretching the polylactic acid composition by a conventional method. In this case, the stretching may be one-stage or multistage stretching of two or more stages, and the stretching ratio is preferably 3 times or more (more preferably 4 times or more, particularly preferably 4 to 10 times) from the viewpoint of producing a high-strength fiber. . The preheating for stretching may be a plate-type or pin-type contact heater in addition to the temperature rise of the roll. The stretching temperature is preferably in the range of 70 to 140 ° C (more preferably 80 to 130 ° C). Further, the heat treatment after stretching is preferably performed at 170 to 200 ° C. (more preferably 180 to 200 ° C.) under tension. The heat treatment can be performed with a hot roller, a contact heater, a non-contact hot plate, or the like.
The polylactic acid filament thus obtained preferably has a melting peak temperature (melting point) of 195 ° C. or higher by differential scanning calorimetry (DSC) measurement. When the melting point is lower than 195 ° C., it is not preferable because the yarn strength of the filament is lowered due to the thermal history during dyeing or shrinks and becomes hard. The higher the melting point, the better, but 240 ° C. or lower is sufficient.
Moreover, in such a polylactic acid filament, it is preferable that the yarn strength is 2.5 cN / dtex or more (more preferably 3.0 cN / dtex or more) because the fabric strength of the interior material is improved. The higher the upper limit, the better, but in practice it is about 10 cN / dtex. Further, in terms of the texture of the fabric, the single yarn fineness is 0.01 to 20 dtex (more preferably 0.1 to 7 dtex), the total fineness is 30 to 500 dtex, and the number of filaments is within the range of 20 to 200. preferable.
(Weaving and weaving)
Next, a fabric is knitted and woven using the polylactic acid filament. At that time, the filament may be subjected to twisting, air processing, false twist crimping, or the like. In particular, it is preferable that the polylactic acid filament is a false twist crimped yarn because the vehicle interior material exhibits a soft texture. Further, it is preferable that a twisted yarn of about 100 to 600 T / m is applied to the filament because not only the wear resistance of the fabric is improved but also the handleability when the fabric is knitted or woven is improved. In addition, it is preferable to fabricate and weave the fabric using only the polylactic acid filament, but other fibers such as polyethylene terephthalate fiber may be included as long as it is 70% by weight or less based on the weight of the fabric.
The fabric structure of the fabric is not particularly limited, but is a woven or knitted fabric woven or knitted by a loom such as a dobby loom or jacquard loom, or a knitting machine such as a raschel knitting machine, tricot knitting machine, or circular knitting machine. It is preferable. Of course, a non-woven fabric or a fiber structure composed of matrix fibers and heat-bondable fibers may be used. For example, examples of the woven structure of the woven fabric include a three-layer structure such as plain weave, twill weave and satin weave, a change structure, a single double structure such as a vertical double weave and a horizontal double weave, and a vertical velvet. The type of knitted fabric may be a circular knitted fabric (weft knitted fabric) or a warp knitted fabric. Preferred examples of the structure of the circular knitted fabric (weft knitted fabric) include a flat knitted fabric, rubber knitted fabric, double-sided knitted fabric, pearl knitted fabric, tucked knitted fabric, float knitted fabric, one-sided knitted fabric, lace knitted fabric, and bristle knitted fabric. Examples include a single denby knitting, a single atlas knitting, a double cord knitting, a half tricot knitting, a back hair knitting, and a jacquard knitting. The number of layers may be a single layer or a multilayer of two or more layers. Furthermore, it may be a raised fabric composed of a raised portion made of a cut pile and / or a loop pile and a ground tissue portion.
(staining)
Next, the fabric is dyed. The dyeing method is not particularly limited, and the dyeing method may be a conventionally known dyeing method such as beam dyeing, cheese dyeing, package dyeing, or liquid dyeing. The dyeing processing conditions are preferably a dyeing temperature of 110 to 140 ° C. and a dyeing time within 19 minutes (preferably 10 to 19 minutes, more preferably 12 to 18 minutes). If the time for such dyeing process exceeds 19 minutes, the fiber strength of the polylactic acid fiber decreases due to the thermal history during the dyeing process, and the fabric strength of the finally obtained vehicle interior material may decrease. The dyeing temperature is a keep temperature at the time of dyeing and the dyeing time is a keep time at the time of dyeing. In the dyeing process, not only the disperse dye but also auxiliary agents and various functional agents may be contained in the dyeing bath.
Further, prior to the dyeing step, scouring under a weak alkali at a temperature of 50 to 100 ° C. or weight reduction processing at an temperature of 80 to 100 ° C. may be performed under alkaline conditions. Further, it is preferable to perform a dry heat treatment at a temperature of 140 to 180 ° C. before and / or after dyeing.
(Resin impregnation)
In addition, after the dyeing step, it is preferable to apply a resin such as a silicon resin, a polyethylene resin, or a polyethylene terephthalate resin to the fabric by an impregnation method such as a padding method.
Since the polylactic acid filament contained in the fabric is coated with the resin by the impregnation treatment, the fiber strength of the polylactic acid filament contained in the vehicle interior material is improved even after the vehicle interior material is exposed to a humid heat environment. This is preferable because it is difficult to lower and an excellent fabric strength is obtained. At the same time, the wear resistance of the fabric is also preferably improved.
At that time, the amount of the resin adhered is preferably in the range of 0.5 to 5.0% by weight with respect to the fabric weight. Furthermore, before and / or after the dyeing process, water-absorbing, water-repellent, brushed, flame retardant, UV shielding or antistatic agent, antibacterial agent, deodorant, insect repellent, phosphorescent agent, retroreflective agent, minus Various processes that provide functions such as an ion generating agent may be additionally applied.
In the fabric thus obtained, the yarn strength of the polylactic acid filament contained in the fabric is preferably 2.3 cN / dtex or more. In particular, 90% or more of the yarn strength of the polylactic acid filament before dyeing is preferably maintained.
Further, in such a fabric, the basis weight is 30 to 1,000 gr / m. ² It is preferable to be within the range. Further, when the fabric is a woven fabric, the cover factor (CF) calculated by the following formula is 1,800 or more (more preferably 2,500 to 4,000), so that the strength of the fabric and the abrasion resistance of the fabric. And preferred in terms of texture.
CF = (DWp / 1.1) ^1/2 × MWp + (DWf / 1.1) ^1/2 × MWf
However, DWp is the total warp fineness (dtex), MWp is the warp weave density (main / 2.54 cm), DWf is the total weft fineness (dtex), and MWf is the weft weave density (main / 2.54 cm).
Further, when the fabric is a knitted fabric, the density of 30 to 100 courses / 2.54 cm and 20 to 60 wales / 2.54 cm is preferable in terms of fabric strength, fabric wear resistance and texture.
(Backing)
The skin material for a vehicle interior member of the present invention may be composed of the cloth alone, but as schematically shown in FIG. 1, a backing resin is applied on either the front or back side of the cloth at a coating amount of 30 g / m. ² Or more (preferably 80 to 120 g / m ² ) Is preferred because the fabric strength is improved. As the backing resin according to the present invention, materials such as acrylic resins, vinylidene chloride resins, latex resins, vinyl chloride resins and urethane resins can be used. Among them, the backing resin is acrylic acid. It is preferable that acrylic resin, such as ester resin, methacrylic ester resin, and acrylamide resin, is included. In addition, as a method for applying the backing resin to the fabric, a conventionally known method may be used. A flame retardant may be included in the backing resin.
As described above, the skin material for a vehicle interior member of the present invention thus obtained has a tensile strength of 400 N / 50 mm or more after being exposed for 1,000 hours in an environment of a temperature of 50 ° C. and a humidity of 95% RH. Is essential. In order to obtain the tensile strength, for example, as described above, a high-density fabric is woven using a stereocomplex polylactic acid filament as a polylactic acid filament, the dyeing time during dyeing is shortened, and the resin is obtained by an impregnation method. Is preferably applied to the fabric and a backing resin is applied to either the front or back of the fabric. By these synergistic actions, the tensile strength after being exposed to an environment of temperature 50 ° C. and humidity 95% RH for 1,000 hours can be 400 N / 50 mm or more.
The skin material for a vehicle interior member according to the present invention has excellent fabric strength even after being exposed to a humid heat environment, and is therefore suitably used as a vehicle interior member such as a car seat skin material, a vehicle floor material, and a vehicle ceiling material. Is done.

Next, although the Example and comparative example of this invention are explained in full detail, this invention is not limited by these. In addition, each measurement item in an Example was measured with the following method.
(1) Weight average molecular weight (Mw)
The weight average molecular weight of the polymer was determined by GPC (column temperature 40 ° C., chloroform) in comparison with a polystyrene standard sample.
(2) Glass transition point, melting point, stereogenicity TA-2920 differential scanning calorimeter DSC manufactured by TA Instruments was used. In the measurement, 10 mg of a sample was heated from room temperature to 260 ° C. at a heating rate of 10 ° C./min in a nitrogen atmosphere. In the first scan, the homocrystal melting temperature, glass transition point, and stereocomplex crystal melting temperature were determined. The degree of stereogenicity was calculated by the following formula.
S (%) = [(ΔHms / ΔHms0) / (ΔHmh / ΔHmh0 + ΔHms / ΔHms0)] × 100
(However, ΔHms0 = 203.4 J / g, ΔHmh0 = 142 J / g, ΔHms = melting enthalpy of stereocomplex melting point, ΔHmh = melting enthalpy of homocrystal)
(3) Tensile strength of filament Using a Tensilon manufactured by Orientec Co., Ltd., which is a constant speed extension tensile tester based on JIS-L-1013 (1999 version), the grip interval is 20 cm, and the tensile speed is 20 cm / min. Measured with
(4) Crimp rate The test filament yarn was wound around a measuring machine having a circumference of 1.125 m to prepare a skein having a dryness of 3333 dtex.
The skein was suspended from a hanging nail of the scale plate, an initial load of 6 g was applied to the lower part thereof, and a skein length L0 when a load of 600 g was further applied was measured. Immediately thereafter, the load was removed from the skein, the scale plate was removed from the hanging nail, and this skein was immersed in boiling water for 30 minutes to develop crimps. The skein after the boiling water treatment is taken out from the boiling water, the moisture contained in the skein is absorbed and removed by a filter paper, and air-dried at room temperature for 24 hours. The air-dried skein is hung on a hanging nail of the scale plate, a load of 600 g is applied to the lower part, the skein length L1a is measured after 1 minute, the load is removed from the skein, and the skein after 1 minute. The length L2a was measured. The crimp rate (CP) of the test filament yarn was calculated by the following formula.
CP (%) = ((L1a−L2a) / L0) × 100
(5) Fabric weight A fabric weight (gr / m ² ) was measured according to JIS L1096.8.5.1 (1999 edition).
(6) Abrasion resistance of fabric Abrasion on a plane was determined according to JIS L1096.88.17.3 C method (1999 version). Grade 5 is the highest and Grade 1 is the lowest.
(7) Texture of cloth Three testers evaluated by sensory evaluation in three stages: (grade 3) soft, (grade 2) normal, (grade 1) hard.
(8) Tensile strength of skin material for vehicle interior member Skin material sample for vehicle interior member based on 8.12.1 standard time, A method (label strip method) described in JIS L1096.8.12 (1999 edition) From the warp direction and weft direction (in the course direction and the wale direction when the sample is a knitted fabric), respectively, and using a textile tensile tester, a grip interval of 200 mm is pulled. The strength at the time of cutting was measured under the condition of a speed of 150 mm / min, and the average value was determined in integers, and was used as the tensile strength of the skin material for vehicle interior members.
(9) Dyeing evaluation The L value was measured using a Spectro Photometer (SD500) manufactured by Nippon Denshoku Industries Co., Ltd. The L value indicates the lightness. The larger the value, the higher the lightness. The closer to 100, the lighter the color is, the closer to white, the closer to 0, the darker the color.
Production Example 1 (Production of poly L-lactic acid)
To 100 parts by weight of L-lactide (manufactured by Musashino Chemical Laboratory Co., Ltd., optical purity 100%), 0.005 part by weight of tin octylate was added, and the reactor was stirred at 180 ° C. in a nitrogen atmosphere with a stirring blade. Then, 1.2 times equivalent of phosphoric acid with respect to tin octylate was added, and then the remaining lactide was removed at 13.3 kPa to obtain chips to obtain poly L-lactic acid.
The obtained L-lactic acid had a weight average molecular weight of 150,000, a glass transition point (Tg) of 63 ° C., and a melting point of 180 ° C.
Production Example 2 (Production of poly D-lactic acid)
To 100 parts by weight of D-lactide (manufactured by Musashino Chemical Laboratory, Inc., optical purity 100%), 0.005 part by weight of octylate was added, and the reaction was carried out at 180 ° C. in a reactor equipped with a stirring blade in a nitrogen atmosphere. For 2 hours, adding 1.2 times equivalent of phosphoric acid to tin octylate, and then removing the remaining lactide at 13.3 kPa to obtain chips. Poly D-lactic acid was obtained. Lactic acid had a weight average molecular weight of 150,000, a glass transition point (Tg) of 63 ° C., and a melting point of 180 ° C.
Production Example 3 (Production of stereocomplex polylactic acid resin)
50 parts by weight of each of the poly L-lactic acid obtained in Production Example 1 and the poly D-lactic acid of Production Example 2 and a phosphate ester metal salt (2,2-methylenebis (4,6-di-tert-butylphenol phosphate) Sodium salt, average particle diameter of 5 μm, 0.1 part by weight of “ADEKA STAB” NA-11) manufactured by ADEKA Co., Ltd. (former Asahi Denka Kogyo Co., Ltd.) is kneaded and extruded at a cylinder temperature of 230 ° C. Was cut into chips with a chip cutter to obtain a stereocomplex polylactic acid resin. The obtained stereocomplex polylactic acid resin had a weight average molecular weight (Mw) of 135,000, a melting point (Tm) of 217 ° C., and a stereogenicity of 100%.
Example 1
(spinning)
The stereocomplex polylactic acid resin obtained in Production Example 3 was dried at 110 ° C. for 2 hours and at 150 ° C. for 5 hours to give a moisture content of the resin of 80 ppm, and then a spinneret having 36 holes of 0.27 φmm was formed. The undrawn yarn was wound up at a speed of 500 m / min after spinning at a spinning temperature of 255 ° C. and a discharge rate of 8.35 g / min.
(Stretching, false twist crimp)
The wound undrawn yarn was drawn 4.9 times with a drawing machine at 80 ° C. by preheating, and the drawn yarn was wound up. Next, the drawn yarn was subjected to ordinary false twist crimping to obtain a polylactic acid false twist crimped yarn (stereo complex polylactic acid filament). The polylactic acid false twist crimped yarn had a fineness of 167 dtex / 36 fil, a crimp rate of 1.4%, a strength of 3.1 cN / dtex, an elongation of 34%, and a melting point of 213 ° C.
(Weaving)
Next, two polylactic acid false twisted crimped yarns are combined and subjected to twisting of 160 T / m, and then placed on warps and wefts to weave a dobby fabric using a normal dobby loom (cover factor) 3534).
(staining)
Thereafter, the fabric was dyed at a temperature of 130 ° C. for 15 minutes using a liquid dyeing machine. At that time, a disperse dye was used.
(Inclusion)
Furthermore, 1.5% by weight of silicon resin was applied to the fabric by a padding machine, dried at a temperature of 130 ° C. for 10 minutes, and then subjected to a dry heat setting at a temperature of 160 ° C. for 2 minutes.
(backing)
Next, for the purpose of improving flame retardancy, a backing resin composed of 20% by weight of antimony trioxide, 40% by weight of decabromodiphenyl ether and 40% by weight of acrylic ester resin is applied to one side of the fabric by a conventional method, and the fabric for car seats (Vehicle interior material) was obtained. At that time, the coating amount of the backing resin during coating was 100 g / m ² .
In the obtained car seat fabric, the basis weight was 550 g / m ² and the cover factor was 3534. The tensile strength after exposure for 1,000 hours in an environment of temperature 50 ° C. and humidity 95% RH was 617 N / 50 mm. The L value was 16.
Example 2
In Example 1, it carried out similarly to Example 1 except using a jacquard loom using a jacquard loom instead of a dobby woven fabric.
In the obtained car seat fabric, the basis weight was 600 g / m ² and the cover factor was 3816. The tensile strength after exposure for 1,000 hours in an environment of temperature 50 ° C. and humidity 95% RH was 430 N / 50 mm. The L value was 16.
Comparative Example 1
Example 1 was the same as Example 1 except that the poly L lactic acid obtained in Production Example 1 was used instead of the stereocomplex polylactic acid resin.
In the obtained car seat fabric, the basis weight was 575 g / m ² and the cover factor was 3711. The phenomenon of shrinkage and curing due to the heat history during dyeing at 130 ° C. was confirmed. In addition, the tensile strength after exposure for 1,000 hours in an environment of temperature 50 ° C. and humidity 95% RH was 140 N / 50 mm, and both the texture and strength could not withstand actual use. The L value was 17.
Comparative Example 2
Example 1 was the same as Example 1 except that the dyeing time for dyeing was changed to 30 minutes.
In the obtained car seat fabric, the basis weight was 540 g / m ² and the cover factor was 3463. Further, the tensile strength after exposure for 1,000 hours in an environment of a temperature of 50 ° C. and a humidity of 95% RH was 325 N / 50 mm and could not be used in actual use. The L value was 15.
Comparative Example 3
Example 1 was the same as Example 1 except that the dyeing time for dyeing was changed to 20 minutes.
In the obtained car seat fabric, the basis weight was 540 g / m ² and the cover factor was 3463. In addition, the tensile strength after exposure for 1,000 hours in an environment of a temperature of 50 ° C. and a humidity of 95% RH was 380 N / 50 mm, which could not withstand actual use. The L value was 15.
[Effects of the Invention] According to the present invention, a skin material for a vehicle interior member composed of a fabric containing polylactic acid filaments and subjected to a dyeing process, which has excellent fabric strength even after being exposed to a humid heat environment. A skin material for a vehicle interior member having the above is obtained.

According to the present invention, a vehicle interior member skin material composed of a fabric containing polylactic acid filaments and subjected to a dyeing process, the vehicle having excellent fabric strength even after being exposed to a humid heat environment A skin material for an interior member is provided, and its industrial value is extremely large.

Claims

A skin material for a vehicle interior member composed of a fabric containing a polylactic acid filament and subjected to a dyeing process, and has a tensile strength after being exposed to an environment at a temperature of 50 ° C. and a humidity of 95% RH for 1,000 hours. A skin material for a vehicle interior member, characterized by being 400 N / 50 mm or more.
However, the said tensile strength shall measure the tensile strength of the skin | leather material for vehicle interior members according to JISL1096.8.12 (1999 version).
The polylactic acid filament comprises (i) poly L-lactic acid (component A) having a weight average molecular weight of 50,000 to 300,000, (ii) poly D-lactic acid (component B) having a weight average molecular weight of 50,000 to 300,000, and (iii) 2) A filament containing a phosphoric acid ester metal salt represented by the following formula (1) or (2) in an amount of 0.05 to 5 parts by weight per 100 parts by weight of the total of A component and B component. Skin material for vehicle interior parts.

(Wherein R 1 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R 2 and R 3 each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and M 1 represents an alkali metal atom. Or an alkaline earth metal atom, and p represents 1 or 2.)

(Wherein R 4 , R 5 and R 6 each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, M 2 represents an alkali metal atom or an alkaline earth metal atom, and p represents 1 or 2)
The skin material for a vehicle interior member according to claim 1 or 2, wherein the polylactic acid filament is a false twist crimped yarn.
The skin material for a vehicle interior member according to any one of claims 1 to 3, wherein the fabric is a woven fabric having a cover factor (CF) represented by the following formula of 1,800 or more.
CF = (DWp / 1.1) 1/2 × MWp + (DWf / 1.1) 1/2 × MWf
However, DWp is the total warp fineness (dtex), MWp is the warp weave density (main / 2.54 cm), DWf is the total weft fineness (dtex), and MWf is the weft weave density (main / 2.54 cm).
The skin material for a vehicle interior member according to any one of claims 1 to 4, wherein the fabric is a knitted fabric of 30 to 100 courses / 2.54 cm and 20 to 60 wales / 2.54 cm.
The skin material for a vehicle interior member according to any one of claims 1 to 5, wherein the conditions for the dyeing process are a temperature of 110 to 140 ° C and a time of 19 minutes or less.
The skin material for a vehicle interior member according to any one of claims 1 to 6, wherein a resin is fixed to the fabric by an impregnation method by 0.3% by weight or more based on the weight of the fabric.
The vehicle interior member skin material according to claim 7, wherein the resin is a silicon resin, a polyethylene resin, or a polyethylene terephthalate resin.
The skin material for a vehicle interior member according to any one of claims 1 to 8, wherein a backing resin is applied to the fabric at an application amount of 30 g / m 2 or more.
The vehicle interior member skin material according to claim 9, wherein the backing resin includes an acrylic resin.
(I) Poly L-lactic acid (A component) having a weight average molecular weight of 50,000 to 300,000, poly D-lactic acid (B component) having a weight average molecular weight of 50,000 to 300,000, and a total of 100 parts by weight of A component and B component A fabric containing polylactic acid filaments containing 0.05 to 5 parts by weight of a phosphate ester metal salt is dyed under conditions of a temperature of 110 to 140 ° C. within 19 minutes,
(Ii) impregnating the dyed fabric with resin,
(Iii) applying a backing resin to the fabric impregnated with the resin;
The manufacturing method of the skin material for vehicle interior members of Claim 1 including each process.
The manufacturing method according to claim 11, wherein the fabric is a woven fabric having a cover factor (CF) represented by the following formula of 1,800 or more.
CF = (DWp / 1.1) 1/2 * MWp + (DWf / 1.1) 1/2 * MWf
(However, DWp is the warp total fineness (dtex), MWp is the warp weave density (main / 2.54 cm), DWf is the total weft fineness (dtex), and MWf is the weft weave density (main / 2.54 cm).
12. The manufacturing method according to claim 11, wherein the fabric is a knitted fabric of 30 to 100 courses / 2.54 cm and 20 to 60 wales / 2.54 cm.